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seen Aug 9 at 17:17

Jul
11
revised Nonlinear FEM and FindRoot
improved formatting
Jul
10
revised Nonlinear FEM and FindRoot
typos
Jul
10
comment FindRoot: getting number of iteration
thanks again for your reply. You are right, here link you can find more about SYS1. It is related with a FEM code. Is that enough for you?
Jul
10
comment FindRoot: getting number of iteration
thanks for your suggestion. I'll look at this documentation
Jul
10
comment FindRoot: getting number of iteration
If I substitute EvaluationMonitor with StepMonitor, I don't know what I get. I my case, FindRootPlot gives 3 steps and 25 residuals. The use of EvaluationMonitor gives back 24, instead StepMonitor gives 1 (I got the same using A) Reap[FindRoot[Sin[x] == Cos[x], {x, 0}, EvaluationMonitor :> Sow[x]]], B) Reap[FindRoot[Sin[x] == Cos[x], {x, 0}, StepMonitor :> Sow[x]]]and C) FindRootPlot[Sin[x] == Cos[x], {x, 0}] (FindRootPlot gives 5 steps and 5 residuals)
Jul
10
comment FindRoot: getting number of iteration
The code iter = Reap[FindRoot[SYS1[XX, UU, F1, fun1] == 0, {UU, U0}, EvaluationMonitor :> Sow[UU]]] works, but I obtain how many times the residuals is computed.
Jul
10
comment FindRoot: getting number of iteration
how can I apply your code at my case? My function is like F[x,par] = 0. I tried with iter = Reap[ FindRoot[SYS1[XX, @UU, F1, fun1] == 0, {UU, U0}, EvaluationMonitor :> Sow[UU]]], but it does not work
Jul
10
asked Nonlinear FEM and FindRoot
Jul
10
asked FindRoot: getting number of iteration
Jun
3
accepted How to set initial guess in NDSolve
Jun
3
comment How to set initial guess in NDSolve
Thanks very much for your reply and sooty for this delayed reply, but I got some troubles in real life! Your answer seems to fit what I wanna do. I'll try with this!
Jun
3
comment How to set initial guess in NDSolve
Sorry for this delayed reply, but I got some troubles in real life! When you solve a nonlinear differential equation using a fem approach (or simply a nonlinear system using a newton method) you need a guess initial value for "each" point before starting your loop cycle. I want to do something similar using NDSolve
May
30
comment How to set initial guess in NDSolve
Thanks again for your reply. Using a shooting method, you give a "suggestion" only for the value of the function and its derivative a fixed point. I'd like to pass "all points" of the initial guess (for instance, a linear function between my bcs). Is it possible to do that?
May
30
comment How to set initial guess in NDSolve
@Szabolcs Thanks for your reply, you are right, I adjusted my code. I'd like to know how to add the initial guess without using shooting method.
May
30
revised How to set initial guess in NDSolve
added 2 characters in body
May
30
asked How to set initial guess in NDSolve
Dec
14
comment How to solve a stiff nonlinear second-order ode?
@ Michael:if you have time, should you have a look at the "original" problem? mathematica.stackexchange.com/questions/38798/…
Dec
13
comment How to solve a stiff nonlinear second-order ode?
@ Michael thanks again for your answer, it is extremely accurate!
Dec
13
accepted How to solve a stiff nonlinear second-order ode?
Dec
12
awarded  Supporter